Abstract: | The Crystal Structure of Tetrakis(di-tert.-butylphosphino)diphosphane [(tBu)2P]2P? P[P(tBu)2]2 [(tBu)2P]2P? P[P(tBu)2]2 1 obtained at ?20°C from a solution of (tBu)2P? P=P(Br)tBu2 forms yellow crystals (regular hexagons). 1 crystallizes monoclinic in the space group C2/c with a = 2145.6pm, b = 1137pm, c = 1696.1pm, β = 110.075° and Z = 4 formula units in the elementary cell. Due to high steric load the bond angles at the tertiary P atoms with δ = 115.7° are significantly larger than those at the primary P atoms with δ = 108.6°. |